(a) Field of the Invention
The present invention relates to a fuel cell system having an ejector that stably supplies fuel and moisture to a fuel cell stack that produces electric energy by using the fuel and air to stably produce electricity.
(b) Description of the Related Art
Fuel cell vehicles operating via a fuel cell system often supply hydrogen (as fuel) to a fuel cell stack to produce electricity via an electrochemical reaction. This electricity is then used to power an electric motor to drive the vehicle. As such, a fuel cell system is a kind of power generation system that electrochemically converts chemical energy of fuel directly into electric energy in the fuel cell stack without converting the chemical energy of the fuel into heat by combustion.
In the fuel cell system, high-purity hydrogen is typically supplied from a hydrogen storage tank to a fuel electrode (anode) of the fuel cell during operation and air from the atmosphere is supplied directly to an air electrode (cathode) of the fuel cell via an air supply device such as an air blower.
The hydrogen supplied to the fuel cell stack is generally separated into a hydrogen ion and an electron as a catalyst of the fuel electrode (anode) and the separated hydrogen ion moves toward the air electrode (cathode) through a polymer electrolyte membrane. Oxygen supplied to the air electrode is combined with the electron that enters the air electrode through an external conducting wire to generate electric energy while generating water.
In order to properly operate a fuel cell, moisture needs to be appropriately maintained in a membrane electrode assembly (MEA) of the fuel cell stack, and a humidifier should be installed on each fuel circulation line and air circulation line that circulates the stack to operate the stack effectively.
However, this humidifying device/system is conventionally disposed outside the stack and thus requires additional space within the vehicle and often involves a complicated pipe connection.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.